This paper presents, for the first time, a detailed study, from an archaeological perspective, of the morphological characteristics of the starch grains within the kernels of selected native wild grasses found in the Central Pampas of Argentina. We compared native wild grasses to maize starch grains, which can be distinguished from each other based on their size, shape and other attributes. The majority of the studied grains did not share morphological characteristics with maize starch grains. Considering this, it can be said that, if irregular and polyhedral grains with transverse or radial fissures dominate the starch assemblage, maize identification may be done on the basis of both morphology and size. Additionally, this research contributes to the characterization of the starch grains of the Panicoideae subfamily, which includes maize. Several classes of simple and compound starch grains are described and defined for native species of Pooideae, Chloridoideae, Arundinoideae, and Panicoideae subfamilies. The results obtained may constitute a baseline for the future determination of maize and wild grass use in archaeological contexts belonging to Middle/Late Holocene hunter-gatherers in the Pampas of Argentina and neighboring areas. Highlight: • Differentiation of maize starch from South American wild grasses by means of their morphology and size.

The shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora.

Proustia is an Andean genus traditionally considered to have three species and ten infraspecific taxa, which has often been placed in tribes other than Nassauvieae mainly because of its distinctive style features. Currently, each of the three species of Proustia is included in its own section denoting a consistent morphological variability within the genus. The heterogeneity among Proustia species mainly relies on habit, spiny structures arrangement, capitula arrangement, and pappus features. On the contrary, the forms or varieties within each species are apparently more homogeneous. The phylogenetic analysis performed here is based on morphological features and includes all the species, and all but two varieties and forms of Proustia. We test the boundaries of Proustia and the hypothesis that morphological discontinuities in the genus are phylogenetically uninformative. A total of 26 taxa and 29 morphological, anatomical, and palynological characters were studied. A maximum parsimony analysis yield six most parsimonious trees that showed almost identical topologies. Our results do not support the current generic concept of Proustia. Independently, each species of Proustia was monophyletic when taxa at sub-specific level were considered. Proustia pyrifolia was retrieved sister to the genus Berylsimpsonia although this clade did not obtain significant support. The spiny structures usually referred to as diagnostic for Proustia are not homologous for the genus. Characteristics of habit, spiny structures, secondary inflorescences and pappus support clades representing each species of Proustia, which may in turn, represent different genera.

No abstract